mc ##der ##mit ##t calder ##a is a prominent geologic feature in the trout creek mountains . the oval @ - @ shaped calder ##a is a collapsed lava dome that st ##rad ##dles the oregon – nevada border on the eastern side of the range and south of the oregon canyon mountains . it is about 28 miles ( 45 km ) long and 22 miles ( 35 km ) wide . the lava dome was created by volcanic eruptions in the early miocene . a total of five large ash flows were produced along with a large r ##hy ##oli ##te dome structure . the calder ##a formed when the dome collapsed about 16 million years ago . the calder ##a contains significant ore deposits ,
mcdermitt caldera is a prominent geologic feature in the trout creek mountains. the oval @ - @ shaped caldera is a collapsed lava dome that straddles the oregon – nevada border on the eastern side of the range and south of the oregon canyon mountains. it is about 28 miles ( 45 km ) long and 22 miles ( 35 km ) wide. the lava dome was created by volcanic eruptions in the early miocene. a total of five large ash flows were produced along with a large rhyolite dome structure. the caldera formed when the dome collapsed about 16 million years ago. the caldera contains significant ore deposits,